The invention relates to a two-stroke internal combustion engine having one or more pistons preferably mounted in pairs coaxially for equal movements on opposite strokes, with a crankshaft which may be located between these pistons, wherein the faces of the pistons lying adjacent the crankshaft are designed to participate in the air inlet stroke, and an air inlet port, and an outlet port for the waste gas are arranged on opposite sides of and near the longitudinal centre of the piston chamber.
According to my own earlier invention a two-stroke oscillating piston engine has been proposed (see my U.S. Pat. No. 4,414,927) in which the fresh air supply channels are located in the cylinder casing and the piston rod is guided to ensure straight line movement in the cylinder housing.
German published specification No. DE-OS-3029287A1 to Franz Stelzer discloses a two stroke internal combustion engine in which the fresh air supply channels having a hollow cylindrical cross section are arranged longitudinally of the piston rod.